C 2500 Truck 2WD V8-5.7L VIN R (1997)
Evaporator Core: Testing and Inspection
One of the most difficult leaks to find is in the evaporator core. To leak test the core:
1. Turn the blower fan on "HIGH" for 15 or more seconds then turn it off.
2. Wait 10 minutes.
3. Remove the blower motor resistor.
4. Insert the leak detector probe as close to the evaporator as possible. If the detector goes to a solid alarm, a leak has been found.
5. If possible, visually inspect the core face with a flashlight for evidence of refrigerant oil.
